we have a php-script wich has a running-time of about 10 minutes. but after about 6 minutes we get an "Proxy Error".but the php-script does its work correctly and is also running after getting this error-message, so we think the apache-proxy-server who forwards the requests to the zend-core-apache-server exeeds the timeout.

what do we have to modify to increase this timeout(to run php-scripts >10min)?

IMHO switch to ZendServer. There's no reserve-proxy anymore and it's also ways faster so you wouldn't have to wait for ten minutes. But be aware, that the browser probably stops waiting for a response after a while. That's why I think a user shouldn't have to wait for ten minutes for a script to finish.

The isn't accessible by means of any official store of any OS connection. Neither would android be able to clients get to it from the Play Store, nor would it be able to be gotten from the App Store or Windows Store for their separate OSes. The application is accessible just as an record, which can be downloaded from a few sources on the web alongside the official site.